Mystery RNC speaker: Will Clint Eastwood make Republicans feel lucky?

There's an open spot in the schedule for the final night of the Republican National Convention Thursday (Aug. 30), and reports point to
Clint Eastwood as the man to fill it.

The Oscar-winning actor and director, who recently endorsed Republican nominee
Mitt Romney, is the likeliest suspect, with a party source
telling Fox News Eastwood is the mystery speaker. Other names floated include 2008 vice presidential candidate
Sarah Palin, former presidents
George H.W. and
George W. Bush and New York Jets quarterback
Tim Tebow -- although the Jets have a preseason game scheduled for Thursday night in Philadelphia.

Speculation about the mystery speaker started swirling earlier in the week with the inclusion of a "TBA" speaker on Thursday night's schedule, in between a performance by former "American Idol" winner
Taylor Hicks and a speech by Florida Sen.
Marco Rubio, who will introduce Romney to the crowd in Tampa.

Eastwood is a long-time Republican supporter, but he stirred up some controversy earlier this year by appearing in a
Super Bowl ad for Chrysler. Some observers read the ad as an implicit endorsement of the auto-industry bailout of 2008-09 that bridged the end of the Bush and beginning of the Obama administrations.

Eastwood -- or whoever the mystery speaker turns out to be -- will take the stage between 9 and 10 p.m. ET Thursday.